1. Field
The following description relates to a discovery technique of a network node in a large-scale distributed network, and more particularly, to an apparatus and method that determine a random back-off time of a plurality of network nodes in a large-scale distributed network.
2. Description of the Related Art
As a ubiquitous society that is a communication environment capable of always being connected to a network regardless of time and place has been realized, a large-scale distributed network which is required to provide services for a large-scale object in a variety of fields has increased. In the large-scale distributed network, directory-based discovery methods have fatal defects such as single point of failure. To overcome these defects, in recent years, a directory-less discovery method has been proposed in a discovery protocol of real-time publish-subscribe (RTPS).
A directory-less discovery does not separately provide a server for managing a network, and therefore, a whole network is prevented from going down due to damage or destruction of the server. For this, each node participating in communication transmits a discovery message for discovery. In this instance, in a case of the large-scale network, a large number of nodes simultaneously transmit the discovery messages, and therefore, a discovery speed of the whole network may become significantly slow, or the network may go down.
In the large-scale distributed network, the nodes simultaneously transmit the messages for discovery on the network, and a large amount of traffic is generated in the network at a time to cause collision, and therefore, communication in a corresponding network may be greatly delayed, or the network may go down.
In other words, when the large number of nodes simultaneously transmit the messages for discovery to find each other, traffic close to or exceeding a maximum transmission rate of the network is momentarily generated, so that communication over the whole network may not be performed smoothly or may even be cut off.
In addition, discovery is randomly performed at the time of initial discovery, and therefore, a desired discovery object may not be easily found, depending on a situation.